1. Field of the Invention
The present invention relates to switches and, more specifically, to vehicle steering column mounted switches for controlling vehicle operating circuits and components.
2. State of the Art
The evolution of steering column switches in motor vehicles has been toward greater integration of functions in a single switch lever. Previously, a plurality of individual switches, each controlling a single vehicle function, i.e., turn signals, windshield wipers, headlights, etc., were mounted on the vehicle dashboard. Current steering column switch levers are designed to control a variety of functions for vehicle operating circuits or devices, such as turn signals and hazard lights, high beam and low beam headlights with optional flash-to-pass, parking lights, fog lights, windshield wiper and wash functions, including multi-speed wipers with or without intermittent delay.
Typically, a steering column stalk switch includes a single lever or stalk pivotally mounted on one side of a housing attached to the vehicle steering column in an easily accessible position for access by the driver of the vehicle. The lever is gimballed at one end in housing so as to move in one and, typically, two mutually separate planes. Further, the lever may be provided with a rotatable end cap, and/or a slidable member movable along the longitudinal axis of the lever to control additional vehicle operating circuits. An intermediate member on the lever may also be rotatable to control another vehicle circuit or device. Actuators are mounted in the housing and, in response to movement of the lever in different directions or planes, rotation of the end cap, or movement of the slidable member, or rotation of the intermediate member on the lever, move a switching member carrying contacts between various switching positions to effect the switching of electrical connections for a particular vehicle operating circuit.
In some vehicles, particularly vehicles manufactured in Europe and/or Japan, two steering column stalk switches are provided, one mounted on the left side of the steering column and one on the right side of the steering column. The various vehicle operating circuits or devices described above are split between the two stalk switches, with the left stalk switch typically controlling vehicle headlight, parking light, fog light, flash-to-pass operation as well as turnsignal operations. The right mounted stalk lever typically controls windshield wiper, mist and wash devices.
However, regardless of whether one or two stalk switches are employed in a vehicle, vehicle design constraints require that the stalk switch lever and the housing assembly be as small as possible while at the same time providing easy access to and movement of the various switches on the stalk switch(es). At the same time, each stalk switch must meet further design constraints relating to a low manufacturing cost, a minimal number of individual components, ease of assembly, and ease of installation in the vehicle. Such stalk switches must also have the capability of easy modification to different vehicle design parameters, such as the ability to control when the vehicle fog lights are operable with respect to the state of the vehicle high beam or low beam headlights. It would also be desirable to provide a vehicle mounted steering column stalk switch which is capable of three modes or degrees of motion, namely, radially, axial and gear driven to operate a plurality of electrical circuits in the vehicle. It would also be desirable to provide a vehicle mounted steering column stalk switch which has the capability of operating a plurality of auxiliary circuits in a single stalk switch lever.
The present invention is a multi-function switch lever apparatus mountable on a vehicle steering column.
The apparatus includes a housing mountable on a vehicle steering column. A lever is pivotally mounted on the housing for movement about at least one and preferably two mutually exclusive axes with respect to the housing. A first contactor is mounted in the housing for movement between positions and carries contacts engagable with conductive elements connected to vehicle device operating circuits. A first actuator is mounted on the lever for movement independent of the lever. A shaft extends through the lever and has first and second ends. The first end of the shaft is fixed to the first actuator for movement of the first actuator. A gear is fixed on second end of the shaft. A toothed rack is movably mounted in the housing in engagement with the gear and carries the first contactor.
Movement of the first actuator, such as through rotation, causes rotation of the gear and movement of the toothed rack moving the first contactor between positions and switching contacts on the first contactor between different conductive elements in the housing to open or close different vehicle operating circuits.
Preferably, the toothed rack is a linear rack.
In one aspect of the invention, a tubular member is mounted over the shaft co-axial with the lever. The tubular member has an internal surface formed with at least two or more detents. A detent follower on the shaft is rotatably engagable with the detents to define at least two distinct positions of the tubular member with respect to the lever. The tubular member is preferably fixed to the shaft for simultaneous rotation of the shaft and gear with rotation of the tubular member between the detents positions.
In another aspect of the invention, a carrier is mounted in the housing. A second contactor is mounted on the carrier and selectively engages conductive traces in the carrier upon movement of the carrier between distinct positions. A plunger is mounted on the carrier and rotatably engages a detent surface formed in the housing to latch the carrier in one of two rotated positions from a center normal position.
A cancel pawl extends from the housing and is engagable with a rotatable member on the vehicle steering column. A pair of cancel members are mounted in the housing and engaged by the cancel pawl upon pivotal movement of the cancel pawl to return the carrier to the center position. Means are provided for biasingly mounting each of the cancel members permitting disengagement of the cancel pawl from the cancel members when the cancel members are held in one of the rotated positions.
The multi-function steering switch lever of the present invention affords several improvements over previously devised vehicle steering column stalk switches. The present switch lever apparatus is capable of providing user actuated control of headlamp operation between off, park, low beam and high beam states, fog lamp on and off switching and control of the brightness of the interior vehicle instrument panel lighting. At the same time, these multiple functions are provided in a small compact lever affording easy construction with a minimal number of separate components as well as easy installation in a vehicle in a minimal amount of space.
In another aspect of the invention, the present switch lever has a unique cancel jam feature which prevents the jam and potential breakage of internal switch components when a driver continues to forcibly hold the turn signal lever in either a left turn or a right turn position while completing the turn. Cancel members in the turn switch mechanism are biased thereby allowing the cancel pawl to slide past the cancel members without breakage.